arm: mvebu: Use dw-apb-uart instead of ns16650 as UART driver

The UART controller used in the Armada 370 and Armada XP SoCs is the
Synopsys DesignWare 8250 (aka Synopsys DesignWare ABP UART). The
improper use of the ns16550 can lead to a kernel oops during boot if
a character is sent to the UART before the initialization of the
driver. The DW APB has an extra interrupt that gets raised when
writing to the LCR when busy. This explains why we need to use
dw-apb-uart driver to handle this.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

diff --git a/arch/arm/boot/dts/armada-370-xp.dtsi b/arch/arm/boot/dts/armada-370-xp.dtsi
index cf6c48a09eacf36e84b4caf4b83be0c35d0b22e8..4c0abe85405fe533ba0cedd41c95d4b9de4b4dc7 100644 (file)
--- a/arch/arm/boot/dts/armada-370-xp.dtsi
+++ b/arch/arm/boot/dts/armada-370-xp.dtsi
@@ -50,17 +50,19 @@
                ranges;
 
                serial@d0012000 {
-                               compatible = "ns16550";
+                               compatible = "snps,dw-apb-uart";
                                reg = <0xd0012000 0x100>;
                                reg-shift = <2>;
                                interrupts = <41>;
+                               reg-io-width = <4>;
                                status = "disabled";
                };
                serial@d0012100 {
-                               compatible = "ns16550";
+                               compatible = "snps,dw-apb-uart";
                                reg = <0xd0012100 0x100>;
                                reg-shift = <2>;
                                interrupts = <42>;
+                               reg-io-width = <4>;
                                status = "disabled";
                };
 

diff --git a/arch/arm/boot/dts/armada-xp.dtsi b/arch/arm/boot/dts/armada-xp.dtsi
index 367aa3f94912ac9d78a35d22321c64667af406cf..8a85ffe77f030214d29af7ce7221dd88d9e0fc9c 100644 (file)
--- a/arch/arm/boot/dts/armada-xp.dtsi
+++ b/arch/arm/boot/dts/armada-xp.dtsi
@@ -42,17 +42,19 @@
 
        soc {
                serial@d0012200 {
-                               compatible = "ns16550";
+                               compatible = "snps,dw-apb-uart";
                                reg = <0xd0012200 0x100>;
                                reg-shift = <2>;
                                interrupts = <43>;
+                               reg-io-width = <4>;
                                status = "disabled";
                };
                serial@d0012300 {
-                               compatible = "ns16550";
+                               compatible = "snps,dw-apb-uart";
                                reg = <0xd0012300 0x100>;
                                reg-shift = <2>;
                                interrupts = <44>;
+                               reg-io-width = <4>;
                                status = "disabled";
                };
 

diff --git a/arch/arm/configs/mvebu_defconfig b/arch/arm/configs/mvebu_defconfig
index a702fb345c01e5693d82f22d0eeb5fc2d7c88b2a..b5bc96cb65a79d87c2f65814e9cc4fecd69e4df1 100644 (file)
--- a/arch/arm/configs/mvebu_defconfig
+++ b/arch/arm/configs/mvebu_defconfig
@@ -33,9 +33,7 @@ CONFIG_MVNETA=y
 CONFIG_MARVELL_PHY=y
 CONFIG_SERIAL_8250=y
 CONFIG_SERIAL_8250_CONSOLE=y
-CONFIG_SERIAL_OF_PLATFORM=y
-CONFIG_I2C=y
-CONFIG_I2C_MV64XXX=y
+CONFIG_SERIAL_8250_DW=y
 CONFIG_GPIOLIB=y
 CONFIG_GPIO_SYSFS=y
 # CONFIG_USB_SUPPORT is not set